Agenda items:

1. Status of REF1 and REF2 simulations

2. Status of 2-deg model tuning

3. Running on ES and Columbia

4. Possibilities for running at BCS

5. WACCM documentation and WACCM website

6. Discussion of available resources vs. research needs

WACCM Meeting: 10/13/2005

1. Status of restrospective and REF2 simulations

Simulations Period Short description of simulation (e.g. REF1)

Status No of simulations in ensemble

REPRODUCING THE PAST

1950-2003

REF1 (w/o QBO) completed 3

• ozone and temperature trends in good agreement with observations; water vapor trends do not agree, and are highly uncertain when computed over short periods (10-12 years)

MAKING PREDICTIONS

1975-2050

REF2 1 realization completed

1 available now (2 more are planned)

• simulations show ozone recovery beginning after ~2010–2015; 1980 ozone levels reached in the 2040’s

Ozone and temperature trends (REF1)

SSU + MSU 1979-1998

SAGE-I 1979-1981 and SAGE-II 1984-2000

Comparison of simulated and observed zonal-mean T trends, 1979-1998 in the stratosphere

Comparison of simulated and observed zonal-mean ozone trends, 1979-2000 in the stratosphere

O3 depletion and recovery in Antarctica, 1975-2045 (REF2)

CLOy 86°S 1 mb

O3 column 86°S

Chlorine loading, peaks in late 1990’s

Antarctic ozone column. Maximum depletion occurs in late 1990’s; recovery begins after ~2010-2015; 1980’s levels reached in 2040’s (series smoothed with a 12-month running mean)

2. Status of 2-degree model tuning

• Fabrizio, Byron have been tuning the model on Bluesky, Bluevista, Earth Simulator

• Model still has at least two important biases/problems

• SH cold pole bias; exacerbated by ozone hole interactive chemistry; breakup of SH vortex occurs too late; ozone depletion persists into January

• NH winter: smaller number of sudden warmings than observed; breakdown of NH vortex is also too late

Estimated machine comparison for 96 CPUs

MachineSimulation yrs/wall

clock day

Bluesky 0 .9

Bluevista 1.6-1.9

ES 2.75

Columbia 1.3

3. Running on ES and Columbia

Decomp Hybrid2-D

DecompCPUs stepon dynpkg physpkg trac2d d-p coup

24x2x2 Y Y 96 849 197 500 95 149

32x3x1 N Y 96 867 210 515 100 140

32x1x3 Y N 96 1625 625 672 314 87

32x4x1 N Y 128 892 224 544 81 120

32x2x2 Y Y 128 945 214 547 87 181

24x3x2 Y Y 144 1143 255 673 114 211

Performance of a 5 day simulation on an Altix node on Columbia. All times are in seconds.

4. Possibilities for running at BCS

• Visited Barcelona Supercomputing Center (BCS) in september

• Presented proposal to do retrospective and prognostic simulations with 2° model (essentially REF1 and REF2)

• Proposal was well received; we have been offered the equivalent of 500 model years of computing resources at BCS

• Stacy will need to ascertain that the model can be run efficiently at BCS (IBM pc970 (G5) system, 2 CPUs/node, 4 GB/node, Myrinet)

5. WACCM documentation and website

• Byron has written a draft WACCM3 document, which has been circulated to WACCM group

• Need to fill in sections on chemistry, MLT physics

• WACCM website needs to be updated with WACCM3 documentation and instructions for download

• Model will be made available as is: no support for implementation

• Timetable for completion?

6. Computing resources vs. research needs

• Resources

• ES: ~ 300 model-years available at 2°• Columbia: ~ 300 model-years at 2°• BCS: ~ 500 model-years at 2°

• CSL account: 9000 GAU (~15 model-years at 2°) /month• ESSL account: 3000-4000 GAU (~ 5-7 model-years at 2°)/month

available through end of 2006

• Note: need to write new CSL and ESSL proposals by end of 2005

• Research

• Complete 2 additional realizations of REF2 at 4°• Solar cycle simulations (2 x 100 years + control; all at 2°)• Retrospective/prognostic (REF1/REF2) simulations at 2°• Other?

1.9 x 2.5 degree runs, 1995 gases, climatological SST

1900 1910 1920 19301930 1940 1950 1960 1970 2030

Control, 1995 smin

smax

Smax, QBO E

Smax, QBO W

Smin, QBO E

Smin, QBO W

Solar Cycle

Solar Cycle + QBO

QBO Bluevista

Columbia

ES

Columbia